I'm using win8.1 and never had this issue in previous versions, even with win8, and its bugging me for a long time coz I RANDOMLY find the solution but the next time it happens that solution won't work anymore

I'm using a Broadband Connection to connect to internet, and am sharing it with another computer through wired network, 

the other computer is using win8 Enterprise and I'm using win8.1 Enterprise the connection is also Wired

it happens ALWAYS after putting one of the computers to sleep, it happens to the other computer that's still ON

this is a video I made to show what happens exactly(10sec)

http://youtu.be/Hu7BxUBpdNk

here's the solutions that works randomly, with "collaboration" with each other most probably

1. disabling and enabling network connection (Ethernet)

2. stop/start  "Internet Connection Sharing (ICS)" service (which must be done after everytime if any of the computers wakes up from sleep to use the other       computer's internet connection)

3. restarting the router 

4. restarting both computers

5. changing the Default Gateway to 1 (to directly connect router)

6. changing the DNS server

from the above options, two of them are more verified, restarting the computer and router or changing the default gateway to 1

sometimes I can't even connect to the router via 192.168.1.1 in browser, but after few times refreshing it resolves and also the issue afterward

what I know is its NEW, WEIRD and RANDOM, I couldn't find and concrete solution so far

I can't use PPPoE due to ISP restrictions,

all of the drivers are up to date last time I checked

my router (Board ID) is D-Link 2540U

Hello James Royce the 3rd,

Do you mean that this issue only occur when one computer connect to the router and another is in sleep mode?

Please take the following steps for troubleshooting:
1. Update the network driver from the manufacturer website
2. Go to Control Panel\All Control Panel Items\Troubleshooting\All Categories and run the Internet Connection troubleshooter
3. Try to use another router and check if the issue still exists

Best regards,
Fangzhou CHEN